The bodies of some of the 50 people who commit suicide on the London Underground every year are often kept in cleaning cupboards and storerooms until an undertaker arrives, according to a sensational new documentary.

Confessions From The Underground, Channel 4’s new documentary, which airs tonight at 10pm, will broadcast unidentified Tube staff making the shocking claims.

The practice, described as “disrespectful” by one worker, is apparently carried out to keep the world’s oldest subway system moving.

A member of the Tube’s Emergency Response Unit said: “As far as I understand it, London Ambulance services have limited resources and a few years back they stopped taking anybody who’s deceased into their ambulances back to hospitals.

“Unfortunately, we had to use, at Stratford, a bin store outside in the car park, you know the big, massive industrial bins. Putting somebody’s body in there, not in the bin, in with the bins, it’s not really respectful.

Another staff member talked of how employees were distressed by the practice of hiding bodies from the public in cupboards.

She said: “I know that we’ve got a store cupboard that we put the bodies in and there is one station supervisor who will not go in that cupboard at all.”

Another added: “We’ve even heard of situations where cleaners come down to get a mop or a bucket or whatever and there’s some poor unfortunate person’s body in there.”

One staff member described his fears about the overcrowding on the system. He said: “There was this one time, when it was just me and this other guy, two members of staff trying to deal with 5,000 passengers, all trying to get through this one particular gate line.

“And you’re under pressure you know to keep the station open.

“I think my ultimate fear is that there’s gonna be too many people down on the platform and I’m gonna be sat in front of a judge and he’s gonna be saying, 'how come you let so many people go down there?'

He added: "The film-makers and Channel 4 were given numerous opportunities to put these claims to me directly, including an interview on camera. They declined."

A London Underground spokesman told the Telegraph: "Following agreed procedures, a body may be moved to a secure room within the station to await collection by undertakers.

"We believe our staff do a fantastic job in responding to such difficult circumstances and they are offered counselling support, if necessary.”

A Channel 4 press release ahead of tonight's screening said: "This documentary provides a rare glimpse into the depths of the iconic Tube network that passengers don't see, as workers reveal the dilemmas and pressures that they must reconcile to keep this hugely complex and strained system running."